Questions tagged [optics]
Optics is the study of light, and its interaction with matter. It includes topics such as imaging systems, fiber optics, lasers, quantum optics, and more.
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Conflicting lensmaker's equation representation
I keep finding these two conflicting forms of the lensmaker's equation. I understand that (n2-n1)/n1 is the same as (n-1) if referring to a lens in air, but I can not make sense of why the reciprical ...
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Justification of the relationship $s/S<\lambda/d$ for interference fringes to be seen
[My book] (NCERT Class 12 Physics text; Chapter no.:10 - Wave Optics)
(https://www.google.co.in/url?sa=t&source=web&rct=j&opi=89978449&url=https://ncert.nic.in/ncerts/l/leph202.pdf&...
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How to begin my journey into simulating light-matter interactions?
I am interested in simulating how light interacts with matter. For example, I want to create a 3D heatmap describing how light might scatter in some heterogenous material. But the more I dig into this ...
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How close to reality is my handwaving argument about Fabry Perot interferometers?
Under this answer to https://astronomy.stackexchange.com/q/55437/7982 I wrote a comment where propose the uncertainty inequality roughly written1 as $\Delta E \Delta t \ge h$ or for photons $\Delta \...
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Why doesn't a lens after a diffraction grating affect the optical path difference?
When observing interference fringes one often uses a lens after the diffraction grating to focus the fringes on a screen like this:
At first sight, one might think that after the lens the path ...
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Why does Near Infrared (NIR) light allow deeper imaging in biological tissue in Multiphoton Microscopy?
I have been reading this paper on multiphoton microscopy (https://www.nature.com/articles/nphoton.an.2010.2) and I am very confused about something. Here is a quote from the paper:
"The NIR ...
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Expectation value of vacuum state [closed]
I'm confused about the expectation value of the vacuum state b.
Here's my understating:
the a' and b' are defined by operator a and b which are similar to the annihilation operator. So when we act ...
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What is the field of view in? [closed]
From a fixed point of view of the eyes that is head neck and eye balls, what is the maximum vertical angle of the sky is covered?
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Need help with experimental setup to measure Birefringence [closed]
First message here, sorry if this is scrappy:
I am looking to measure the birefringence of multiple crystalline structures (calcite, ice, etc), and came across this methodology:
Shine a laser at ...
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The use of Corner reflector and beams to find the distance between moon and earth and light Divergence?
I am about to start college and my knowledge regarding both beams and retroreflectors is close to nonexistent ,
but from what I read a corner reflector is a device that reflects waves back to its ...
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Two-qutrit preparation using linear optics
How can I prepare a two-qutrit product state (let's say $\frac{1}{\sqrt{2}}|0\rangle|0+2\rangle$ using optics? Do I need a BBO crystal (as I know BBO crystal produces an entangled state), or can I use ...
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Why transparent object altering only the phase of light but not the frequency or amplitude? Is there exception?
I have learned the fascinating phase contrast microscope from Eugene's textbook optics that made transparent object become visible.
From page 647, he said that
In contradistinction, it is often ...
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Can a system of lenses or compound lens have a higher numerical aperture than a single element in the system?
I am attempting to create a simple Abbe condenser for a microscope, which typically consists of two converging lenses.
Ideally, I would like to achieve a numerical aperture for the condenser of ...
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Is reflection from pockel cell normal?
We are trying to align a laser for a 2-photon microscope and we noticed a reflection from the pockel cell. The reflection can be caught on the edge of the waveplate or the iris that are before the ...
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Measuring Stokes parameters leading to a degree of polarisation greater than one
I am trying to measure the stokes parameters of a laser beam using the rotating waveplate method detailed here:
https://pol3he.sites.wm.edu/wp-content/uploads/sites/50/2020/01/measuring-Stokes-...
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How does a Circular Light Source create Shadows with Darker Edges Sometimes?
Problem:
There is a room where the light fixture is circular*. Shadows of objects in this room are darkest in the center and brighter toward the edges, except for my phone charger. Its shadow is ...
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The impulse response of the Rayleigh-Sommerfeld formulation of diffraction
What is the impulse response for the Rayleigh-Sommerfeld formulation of diffraction? In Goodman's Fourier Optics, two formulations for Rayleigh-Sommerfeld are given, and both of them seem to be ...
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Why are Jones vectors normalized?
I have been studying polarization of light, and everywhere I look, one of the main approaches for dealing with polarization of light is by using Jones Vectors.
These vectors describe the polarization ...
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Paraxial Spherical wave emanating from point source
I'm reading through chapter 5.3.1(Impulse response of a Positive lens), in Goodman's "Fourier Optics"(p.109). An object is placed a distance $z_1$ in front of a lens.
If we place a point ...
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I need to find the dependence of spectral resolution from entry and exit slit width of prism spectromer
I have a prism spectrometer which has two entry slits, two collimating mirrors and a rotating prism. I need to to find the the spectral resolution in respect to the changing width of entry end exit ...
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Getting the spectrum of light source at high intensity (for low transmittance measurement)
I am trying to measure the transmittance spectrum through a liquid sample using a visible-NIR spectroscopy (a spectrometer connected to a fiber optics and a collimating lens at the end), with tungsten-...
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How to derive that Optical path length should be stationary from Fermat's principle?
I read above eq. (5.3) in "Optics" by Eugene Hecht
Fermat's Principle maintains that the optical path length OPL will be stationary; that is, its derivative with respect to the position ...
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Help with sourcing a specific type of integrating sphere
I am looking for a specific type of integrating sphere that can be used to capture diffuse reflectance measurements, and I would appreciate help with locating a commercially availably version of this ...
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Is it possible to combine two (or more) laser beams into one beam with double intensity? What are the caveats of this method?
Here is a schematic for what I mean:
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Is the Fourier Transform a reliable way to infer the physical phenomena producing an RF signal?
Consider the following thought experiments:
Scenario 1:
A person standing far away shines 3 light beams at you, each beam having a narrow spectral distribution centered around different frequencies F1,...
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When does magnification not depend on distance of object? [closed]
Two thin lenses share a common optical axis. Their focal lengths are f1 = 20 cm, respectively and f2=50 cm. In front of the first lens at distance x>f1 there is an item. On the screen behind the ...
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Why the consecutive spherical wavefronts produced by a rest point source are not equidistant? [closed]
I learnt that a point source produces spherical wavefronts and i know the reasoning behind that too and while studying the concept again a question popped in my mind, that "Are those spherical ...
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Is it preferable to say $v$ is " image distance " than to say " image position " in spherical mirror formula?
I was going through spherical mirror formula $1/v + 1/u = 1/f$ where $u$, $v$ and $f$ are named as object distance, image distance and focal length respectively. But while using this equation we do ...
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Can I recover the physical wavelengths present in a light source from a time-series measurement of its amplitude?
Consider a mixture of different wavelengths being emitted from the same point (ex: a star). This light consists of a mixture of wavelengths and intensities at each wavelength. When measuring the ...
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Would the "FFT" of a light source be a reliable indicator of perceived color?
Paraphrasing from here:
A purely monochromatic 575nm wavelength light would be "perceived" as yellow, as would a light that has equal components in red and green (but no yellow). However, ...
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Is it possible to create Fabry-Pérot Interferometer with one partially transparrent and one non-transparent mirror?
In the literature sources I've found so far about Fabry-Pérot interferometer there are only example schematics of the interferometers in transmission - light source is placed from one side of the ...
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450nm peak absorption [closed]
I am looking for an oxide compound (metal oxide, or similar preferably inorganic) which shows light peak absorption at 450 nm. I have troubles in finding the right compound, as most of the oxides have ...
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Absorbance spectrum of common metal oxides
I am looking into metal oxides particles, and I wonder where can I find the absorbance spectrum of visible light of common avaiable metal oxides?
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Based on my calculations, we cannot see the Earth from the ISS. Obviously it's wrong. Why?
What started as a fun exercise really annoys me because I cannot see where I got it wrong.
I initially wanted to see how many photons hit a pixel of a camera on the ISS pointed at the Earth - but I ...
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How would I account for non-linear refractive index effects in a nitrogen based medium?
I am trying to estimate the clamped intensity of a 90 fs femtosecond laser when it passes through a flow of nitrogen that is exiting a nozzle. Prior to the nozzle, the incoming nitrogen flow is heated ...
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Michelson interferometer moving mirror by half wavelength
With expanding beam I understand I will get circular fringes, and I understand if you move the mirror by d the path difference change of the interfering beam is $2dcos\theta$. But I don't understand ...
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Is reflected color not from the wavelength corresponding to that color?
I was reading through Josef Albers' interaction of color (a classical art color theory book), where he makes this point:
If I see a substance, or pigment of a particular color, doesn't that mean I'm ...
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Applying a phase shift to a coherent state vs a phase-space rotation (Mach-Zhender)
I'm having some trouble with the physical implementation of a phase vs rotation in phase-space for a coherent state.
Say I have a laser pulse which yields a coherent state $|\alpha\rangle$, I then put ...
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Derivation of optical resolution
I'm trying to prove optical resolution formula from scratch and im having a hard time doing it. I dont know much about optics (im studying cosmology) and i need a detailed proof of optical resolution ...
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Refraction of light - Huygens' Principle
To elucidate the rationale behind the bending of light as it transitions between different mediums, Huygens' principle is predominantly employed. The procedure, as demonstrated in this video (link: ...
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Difference between Dicke superradiance and dipole-coupled emitter superradiance
This question is similar to "What causes the collective emission in Dicke Model?", but more specific. I wonder if the situation described in
[1] R. H. Dicke – Coherence in Spontaneous ...
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Refractive index from absorbance, transmittance or reflectance spectra of thin film, knowing its thickness
I have absorbance (Abs), reflectance (R%) and transmittance (T%) data of TiO2 deposited thin film on FTO glass substrate. The data was collected using UV-Vis spectrophotometer. Also, I know the ...
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How do you represent a plane wave propagating at an angle $\theta$ w.r.t. $z$-axis? [closed]
There is a plane wave $\exp(i\mathbf{k}\cdot\mathbf{r}-i\omega t)$, where $\mathbf{k}$ is the wave vector. Suppose this wave propagates at an angle $\theta$ w.r.t. $z$-axis. What will be the wave ...
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What's a safe, easily executable experiment to confirm that quantization of light occurs directly to the retina? [closed]
What's a safe, easily executable experiment to confirm that quantization of light occurs directly to the retina.
We know that light is quantized when projected on to a surface, or on to an inanimate ...
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How to calculate refractive index from absorbance, transmittance or reflectance spectra?
I have absorbance (Abs), reflectance (R%) and transmittance (T%) data of TiO2
deposited tin film on FTO glass substrate. The data was collected using UV-Vis spectrophotometer.
How to calculate ...
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What is a true delay line and is there possibly a false delay line?
I'm reading "Silicon nitride passive and active photonic integrated circuits: trends and prospects" and one of discussed application of $\rm SiN$ is "true delay line". All the ...
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Creating a wavelength selectable light source using diffraction grating and broad-spectrum led
Could a miniature wavelength selectable light source (lamp + monochromator) be created by using a broad spectrum led or tiny xenon/deuterium lamp as a light source combined with a small diffraction ...
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How to calculate refractive index $n$ from absorbance, transmittance or reflectance spectra?
I have absorbance (Abs), reflectance (R%) and transmittance (T%) data of $\rm TiO_2$ deposited tin film on FTO glass substrate. The data was collected using UV-Vis spectrophotometer.
How to calculate ...
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Refractive index of titanium dioxide films as a function of wavelength for 400 C ° annealed films
I used UV-Vis/NIR spectrophotometer to extract the measurements of refractive index %R corresponding with wavelengths in the range of 190-1100 nm of TiO2 thin film deposited on FTO glass substrate. ...
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How large is the Group Delay Dispersion for ultrafast light pulse into glass if the refractive index changes linearly?
If an ideal ultrafast pulse with the duration of 1 cycle of light is propagating from air (with n = 1) into glass in the direction normal to the interface, Im also assuming the refractive index n of ...
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